Despite a century of research on vapor bubble dynamics and its ramifications for boiling phenomena, a unified understanding of bubble nucleation at the nanoscale and growth/transition to macrobubbles has yet to be established. Little attention has been paid to establishing fundamental connections between boiling characteristics at the nanoscale and macroscale, which may differ significantly owing to confinement effects [1]}, [2]}. Closing this fundamental gap in knowledge is of paramount importance for fully leveraging the benefits of phase change heat transfer in high-heat-flux applications, including, among others, electronic cooling [3]}, inkjet printing [4]}, and spray quenching [5]}. Starting with the work of Nukiyama [6]}, who heated a liquid by running electricity through a metal wire, early research in this field was devoted to establishing a boiling curve consisting of five regions of pool boiling [7]}: natural convection, isolated nucleate boiling followed by slug nucleate boiling, transition boiling terminating at the Leidenfrost point, and ultimately film boiling.
Research has been focused on fundamental understanding of pool boiling transitions with the aim of achieving practical goals in engineering [3]}, [9]}, [10]}, such as enhancement of the heat transfer coefficient [11]} and prevention of early critical heat flux [3]}. The latter is the limiting heat flux beyond which the heat transfer to the liquid starts to decrease owing to lack of liquid contact with the heated surface because of horizontal coalescence of nucleating bubbles.
